The present invention relates generally to a cartridge system for a probing head for an electrical test probe, and specifically to a probing head cartridge system that includes a main probing head body and a switchable and replaceable probing tip cartridge.
An electronic test probe generally consists of a probing head, a cable, and a connector. The probing head may have an integral or replaceable probing tip that is suitable for making an electronic contact with electrical components. The probing head is attached to a first end of the cable and the connector is attached to the opposite end of the cable.
Electronic test probes are used to provide an electrical connection between electrical components and testing instruments such as oscilloscopes and other measuring, monitoring, diagnostic, and signal processing instruments. As the size of electrical components decrease, probing tips get smaller.
One type of probing head is a complete unit with an integral, non-replaceable tip. Although this type of probing head provides for an electrical connection with very low resistance, if the tip breaks, the entire head must be replaced. Also, an integral tip limits the user to a single tip unless the user replaces the entire probing head.
Another type of probing head includes a head assembly with a hollow socket that couples with a switchable and replaceable probing tip. One example of this type of probing head is shown in U.S. Design Pat. No. 354,923 to Nightingale. One problem with this socket-type-probing head is that the tips often slide out of the socket. Another problem is that the small tips are easily lost and, once lost, hard to find. Examples of other references that disclose probes with replaceable tips include U.S. Pat. No. 4,552,465, U.S. Pat. No. 4,849,689 to Gleason et al., Japanese Document JP11258270A, and Japanese Patent No. 10282140. In general, these replaceable probing tips are easily broken and, once broken, hard to remove and replace.
U.S. Pat. No. 5,334,931 to Clarke et al. (the xe2x80x9cClarke referencexe2x80x9d) sets forth a probing head that may be readily replaced. It is designed with a cantilevered portion that is meant to reduce contact tip breakage. However, if the contact tip does break, it is easy to remove and replace. The Clark reference does not disclose a solution for modern complicated test probes that include expensive electronics and must have little or no inductance.
U.S. Pat. No. 4,209,742 to Bender et al. (the xe2x80x9cBender referencexe2x80x9d) is directed to an electrical probe with a modular form of construction for an old technology modular probing head (signal sensing head), a cable with a plug at both ends, and an output termination. One or both plugs are suitable for connecting to the probing head. If the cable is broken, it is simply disconnected at both ends and replaced. Similarly, the probing head can be disconnected and replaced. Because the Bender reference is directed to old technology, it does not disclose a solution for modern complicated test probes that include expensive electronics and must have little or no inductance or capacitance.
The present invention relates generally to a cartridge system for a probing head for an electrical test probe, and specifically to a probing head cartridge system that includes a main probing head body and a switchable and replaceable probing tip cartridge. The body may include a substantial portion of the electronics that make probing heads expensive. Each cartridge would include a fixed tip. However, the cartridges could be made with different types of tips such as a pointed tip, socket tip, or grabber tip. Those embodiments in which the tips are fixed in the cartridge have significantly lower capacitance than designs in which tips are exchanged within the socket.
A cartridge system of the present invention includes a main probing head body with electronics positioned therein. Further, the cartridge system includes a probing tip cartridge having a probing tip. An electrical contact mechanism electrically couples the electronics to the probing tip when the probing tip cartridge is in mating relationship with the main probing head body. The types may be, for example, a pointed tip, a socket tip, or a grabber tip.